private String makeReturnMsg(String status, List<TaskInfo> taskInfoList) {
XStream xstream = new XStream();
xstream.alias("ReturnMsg", ReturnMsg.class);
xstream.alias("TaskInfo", TaskInfo.class);
ReturnMsg returnMsg = new ReturnMsg();
returnMsg.setStatus(status);
if (taskInfoList != null) {
returnMsg.setTaskInfoList(taskInfoList);
} else {
returnMsg.setTaskInfoList(new ArrayList<TaskInfo>());
}
return xstream.toXML(returnMsg);
}